Answer:
Mucus.
Explanation:
Stomach is a J- shaped organ that lies above the small intestine. Stomach plays an important role in digestion. Stomach secretes the hydrochloric acid, enzymes and the mucus.
The hydrochloric acid produced in the stomach can damage the stomach lining. To protect the stomach from the acid, mucus is released by the stomach. Mucus protects the stomach from the acid.
Thus, the correct answer is option (d).
